In a large bowl, combine all of the ingredients and lightly toss until well combined. If time allows, refrigerate the salsa for at least one hour before serving. Doing this will allow all of the vibrant flavors in this salsa to really come together.
Pre-heat your barbecue or on the stove top, heat a grill pan over medium-high heat.
In a large bowl, combine the lime juice, olive oil, garlic, and cilantro, cumin, chili powder, garlic powder, onion powder, salt, and pepper. Whisk to thoroughly mix.
Toss the chicken breasts in the marinade until evenly coated. (If time allows, let the chicken marinate in the sauce for a few hours)
Place the chicken breasts on the pre-heated grill, pour over any marinade that is left in the bowl. Grill the chicken until it is cooked all the way through or if you are using a thermometer, until it has an internal temperature of 165°F. Top with Avocado-Feta Salsa, and enjoy!